A day after an armed man killed a dozen people at the Navy Yard in Washington. Democrats and gun control activists are already pushing for another look at the nation's gun laws.
But assuming there is some impetus for a new debate, here are a few things the you need to know about it:
1) Appetite for new gun laws spiked after Sandy Hook, but just before that, they were at record-low levels.
And even in the aftermath of Newtown, there were still fewer people calling for new gun laws than there were in the late 1990s and early 2000s.
Here's another look at how multiple pollsters showed support for gun control dropping in the two decades before Newtown:
2) Just six months after Newtown, support for new gun control measures leveled off again.
As these events fade from memory, so does the spike in support for new gun measures. And the months between the Newtown shootings and the Senate vote on background checks meant support for new gun laws and the immediacy of the situation also faded.
3) After Newtown, nearly as many people blamed the episode on an isolated act by a troubled individual as blamed it on broader problems in society.
This suggests that many people don't necessarily see gun culture as the problem, so much as mental health. And given the new reports about Aaron Alexis's history of misconduct and mental health problems, that seems a more likely avenue for legislation that can actually pass.
4) While polls showed overwhelming support for increased background checks (upwards of 90 percent) after Newtown, gun rights advocates were far more vocal than gun control supporters.
In fact, despite the tilt in public support toward background checks, anti-gun control messages were just as frequent as pro-gun control messages on Twitter until the very end of the Senate debate.
5) Gun violence is still not a big priority for Americans.
While shooting tragedies dominate the news when they occur, eliminating gun violence is relatively low on the totem pole for most Americans. A May Gallup poll showed 55 percent thought reducing gun violence should be a top priority -- lower than reforming the tax code and entitlement programs and just slightly higher than reforming the immigration system.